Braking apparatus



April '7, 1936- M. H. LOUGHRXDGE 6,589

BRAKING APPARATUS Filed Oct. 5, 1928 3 Sheets-Sheet 43 43 o 44. o 6/ o. 45 4F 75 52 a? 63 I N VEN TOR.

April 1936- M. H. LOUGHRIDGE 2,036,589

BRAKING APPARATUS Filed 001;. 5, 1923 3 Sheets-Sheet 2 INVENTOR.

1 I UNI-TED STATE Patented Apr. 7, 1936 s- PATENT OFFICE 38 Claims. This invention relates to abrake controllin system and apparatus particularly adapted for tion, and when the iorestalling device isoperated,

railway trains and to an automatic train control system for controlling traihc on a railroad.

The objects of the invention'are to provide 'a braking system which is manually controlled and. which is automatically controlled and in which Fig. 14 is an enlarged sectional elevation 01 the equalizing valve shownin Fig. l in the rethe brakes may be applied or released manually 1 orautomatically, progressively to the extent'desired; a system inv which the manual control suspends the operation of the automatic control only to the extent to which the manual control is efiective and in which the automatic control hecomesoperative as the manual controlis released; a system in which the automatic control requires the operation of a forestaliing device each time it becomes operative to prevent a brake applicathe brake control is subject .to control bythe speed of the vehicle. Another object is to secure an intermittent venting of the train. brake pipe. Another, object of the invention is to providea speed control system using the principle or the venturi tube, designed for movements in. both directions aud tor a variety or speed controls.

Other objects of the invention will appear from the following specification and the accompany- Fig. 1 is a sectional elevation of the brake controlling apparatus,

Fig. 2 is a transverse section on Fig. 3 isa transverse section on line 3-3 of Fig. 1, Y Fig. 4 is'a transverse section of lined-4 of line 2-2 or Fig. l, l

Fig. 5 is a view, partly in section and partly in diagram, showing the connections and operation of the automatic control,

Fig.6 is a plan view of the motion plate and plunger-oi the manual control,

;Fig. 7 is a sectional view oi the control magnet and stepping valve,

Fig.8 is a view of the stepping valve in section,

Fig. 9 is a iragmentary elevation of the speed control device,

Fig. 10 is a longitudinal section of a double ended Venturi tube adapted for speed control purposes,

Fig. 11 is a front elevation, partly in section, oi the Venturi system,

Fig. 12 is a detail showing the method of obtaining direction control in the Venturi tube and Fig. 13 is a circuit arrangement for the controlmagnets.

position.

leased position;

Fig. '15 is a sectional elevation corresponding to Fig. 14 with the equalizing valve in the application position;

Fig. 16 is an enlarged sectional view of the stepping valve shown in Fig. 8 in the released position, and

Fig. 17 is a sectional view corresponding to Fig. 16 with The application mechanism This invention comprises a brake application valve biased by a spring to the most retarding, position and held released by a walking beam one end of which is manually controlled and the other end of which is .controlled automatically. When the manual control is in operation conditions are set up to prevent the operation of the automatic control, but the automatic control remains e1- iective for a'greater degree of braking than is applied by the manual system.

' In the drawings, II is the valve cylinder in which the valve l2 slides, I3 is a cavity in the valve, I4 is an air supply duct, i5 connects to chamber 22, I 6 connects to chamber 20, ll connects to chamber and i8 connects to chamber Hi from the valve cylinder II as will be understood from Fig. 2. This cylinder is normally vented to atmosphere through the passage 30 and when the valve is in the raised or clear position '10. the mechanism in the application shown, the expansion chambers I9, 20 and 2| are atatmospheric pressure and chamber 22 is'connected with the air supply duct I through cavity II.

The chamber 22 connects to the cylindrical'expansion chamber 23 through port 25 (Fig. 14) and has the piston 26 working therein. The stem of piston 26 closes the exhaust port 28 connecting chamber 21 with the exhaust pipe 29 when the piston is in the lower position. When the piston is raised to its fullest extent it closes the aperture 24 connecting chamber 22 with the cavity l3 in the valve. When port 28 is open the train line 32 is exhausted through passage 3! and the brakes are applied in a well known manner proportional to the extent of the exhausting. If the exhausting is restricted, or varied, the brake application will be correspondingly varied. As this is a de--' sirable feature in braking trains, the ports controlled by-piston 26 are varied as the brakes are applied. For instance, raising 26 partially closes 24 and temporarily restricts the exhaust from chambers 22v and 23 until the brake pipe pressure in 21 is reduced below the pressure in 2223. This lowers the piston 25, thereby closing, or partially closing, the vent port 28 until the pressure in 2223 is further reduced through port 24, when piston 26 is again'raised to open port 28 and to partially close port 24. This movement by piston 26 is repeated until chambers 22--23 and the reservoir with which they are connected are equalized in pressure. From this operation, it will be noted that the train line is not exhausted by a continuous flow of air through the vent 28, but instead, the flow is intermittently tapered so that the brakes are applied with increasing pressures which are separated by an interval of time.

The brake pipe 32 connects through passage 3| with the chamber 21. It also connects to the cylinder 33 having the piston 34 normally held in its lower position by the spring 35. The upper portion of piston 34 is subject to the air pressure in chamber 23 through the port 3?. The piston 34 has secured thereto the hollow plunger 36.

which connects with the main reservoir supply pipe MR and when in the lowered position permits the train line 32 to be charged from MR through the port in the side of 36, but when piston 34 is raised due to a lowering of the pressure above the piston, the hollow plunger 36 is raised and the MR pipe is cut off.

The valve I2 is controlled by the plunger 42 and is normally biased to the controlling position by the spring M. The plunger 42 is controlled by the walking beam 43 which is supported at one end by 44 and at the opposite end by 6I.

The manual control The supporting stem 44 is bifurcated at 45 to receive the arcuate motion plate 46 which is provided with oblique slots in steps connecting the parallel slots 5|, 52, 53, and 54, Fig. 6. A pin 41 engaging these slots and the stem 44 moves the stern vertically up and down, in response to movements of the motion plate. The stem 44 terminates in a piston 48 working in the dash pot 49 which is controlled by the valve 50 with the object of cushioning the downward movement of this stem as forced by spring M. The arcuate motion plate is connected at 'I010 to the rotary valve 68 manually operated by handle 69, Fig. 5, as hereinafter described.

The automatic control The end of the walking beam 43 is supported by a second walking beam 6| supported by the plungers 62 and 83. Plunger 62 connects with pis ton 64 in cylinder 65 and plunger 63 connects with piston 65 in cylinder 51. When these cylinders are under air pressure the plungers are raised, both ends'of Walking beam 6| are raised and 43 is raised to its extreme position. When air is exhausted from either of these cylinders the walking beam GI is lowered at one end, correspondingly lowering 43 and when both of these cylinders are exhausted both ends of GI are lowered and 43 is lowered to a greater extent.

The rotary valve 68 is cored at II to fit the projecting end 12 of the valve cylinder and rotates thereon, being held in place by the collar 13. Air passages are enclosed between the lower face of 68 and the top of the application mechanism. which passages are shown diagrammatically in Fig. 5 with the air connections. Cylinder 65 by pipe '14 connects to the slot I5 in 68 and pipe leading therefrom connects to the forestalling device BI and associated apparatus. Cylinder 51 connects by pipe I5 to the slot 11 and by pipe 18 connects to the forestalling device 19. It should be understood that pipes 14, I6, 18 and 80 lead from stationary apertures or passages in the casting of the application mechanism, over which apertures the arcuate slots 75 and 11 move with the rotary valve 68. Air pressure through pipe 84 connects to the arcuate slots 82 and 83 in thev casting below the valve 58. The slot 82 aligns circumferentially with the slot I5 and the slot 83 aligns with the slot TI.

The fo'restaZiing system The forestalling system is manually operated to synchronize with the trackway control as disclosed in U. S. Patent 1,627,567, May 10, 1927. Briefly, this comprises a valve operated by the handle 88 to either of two positions. In the position shown, pipe 80 connects to the interior 05 of the valve member and through port 86 connects to pipe 81 while pipe 90 is closed. When handle 88 is moved to its other position port 86 is closed and pipe 90 connects with chamber through port 89. thus alternately changes the connections between pipes 81 and and pipe 80.

The traclcway controls and stepping valve The magnet 9|, Fig. 7, is controlled from the trackway by any suitabie means such as disclosed in U. S. Patent 1,859,591, May 24, 1932. This magnet controis the valve 93 through the armature 92 and is energized under clear conditions. In the deenergized. position shown it will be noted that the air supply pipe 94 is closed and that cylinder 98 and timing reservoir 91 are exhausted to atmosphere through passage 96; port end alarm whistle 95a. This permits the spring I00 to pull the locking arm IGI and ratchet detent I02 backwards, thereby rotating the ratchet wheel I03 and the stem I04 to the extent of one tooth or step;

When magnet 9| is energized the position of valve 931s reversed, the port 95 is closed and air under pressure from 94 is supplied to timing reservoir 91 and cylinder 98 through passage 96. This moves the piston 99 forward and brings the derent I02 into engagement with the next ratchet tooth, and thus into position to rotate stem I04 and valve I08 another step when 9| is again deenergized.

The ratchet wheel I03 operates a rotary valve I08 Figs. 16-17, which has a double row of ports, one row I05I06a. aligning with pipe 81 and the other row I09-I09a aligning with pipe 90 as indicated by the dotted lines. The ports I06al09 connect with chamber H0 and the ports I 090 and I08 as indicated by the dotted lines connect with the exhaust I05 through the valve body 508. A new pair of ports align with these pipes at each step of the valve, as shown in Fig. 8, which, in the position shown, connects pipe 87 through port I0! to the chamber IIO while pipe 90 connects to exhaust I65, but upon the rotation of valve I08 by one step of the ratchet wheel, pipe 81 is connected to exhaust through I06 and pipe 90 connects to chamber IIO through port I59 and these pipes are alter-, nately connected and disconnected with chamber H0 and exhaust for each step of wheel I03. Chamber H0 through port IIOa. connects with chamber II5c'. housing spring I I5 and with valve cavity I I I, which in the position shown in Fig. 16 connects through port M with the air supply The movement of handle 88 pipe H2. This is the position when magnet 9I is energized, or the release position, but when this magnet is deenergized, the valve H2b is moved to the position indicated in Fig. 1'7 in which the air supply pipe H2 is cut off and the cavity III connects through port H2a with pipe H6. This is caused by the valve 93 permitting the air to exhaust from cylinder 98 through passage 96. A port H3 at the end of cylinder H4 connects this cylinder with cylinder 98 and permits the air pressure to equalize in these cylinders. The spring H5 is adjusted to move the piston H40. and the valve H2b connected therewith to the position shown in Fig. 17 before piston 99 moves to blank the port H3. That is, the air pressure is sufiiciently reduced in cylinder H4 to permit the movement of valve I I2b before port H3 is closed.

When magnet 9| is energized the valve 93 connects the air supply pipe 94 with cylinder 96 and moves the piston 99 to the position shown in Fig. 16, this uncovers the port H3 and admits air pressure to the face of piston H4a, moving this piston to the position shown in Fig. 16. The movement of piston 99 moves the detent I02 to engage another tooth of stepping wheel I03 for the next operation of valve I08. Pipe H6 connects to the speed control device Fig. 9 and under certain conditions maintains the air supply that was cut off from pipe H2 and under other conditions (high speed) pipe H6 is connected to atmosphere thereby leading to a brake application.

.The speed control system Speed control is obtained by restricting the air supply to pipe H6 under predetermined conditions of speed. Under low speed and with magnet 9I deenergized, this pipe is supplied with air under pressure which maintains valve, Fig 1, in the released position, but under high speed this pressure is exhausted, thereby producing a braking efiect. This will be understood by considering the air pressure to cylinder 66 operating the brake valve. This pressure is maintained through pipe I4, slot I5, pipe 80, valve 8|, pipe 81, valve I08, chambers H0, HM, and cavity III to vport H20. connecting to pipe H6 in the application position. The speed control device, Fig. 11 connects pipe H6 to an air supply pipe H1 at a predetermined low speed, or connects this pipe to atmosphere through I31 at high speed. Speed control may be secured in various ways, as for instance by the centrifuge disclosed in U. 8. Patent 1,807,596, June 2, 1931. In the present disclosure speed control is obtained for movements in both directions by a double ended Venturi tube mounted on the vehicle and arranged to vary the air pressure in a cylinder having a valve mechanism, proportionally to the speed of the vehicle.

In Fig. 10, the side of the vehicle is indicated by I2I in which flared apertures A and B are provided leading to the tapered Venturi tube I21 with the restrictedorifice in the centre at I23. The crescent shaped projections I22 may be provided to direct the air into the tubes A and B by increasing the air "pressure .at the entrance of the leading tube and creating a partial vacuum at the orifice of the following tube. The outer apertures may be supported in the centre by the collar I24 as shown. Mounted on the axial centre at the narrowest part of the tube are the smaller double ended tubes I25-I26. These are supported by the valve head I29 formed integral with casting I24 and having a passage I3I connecting with the cylinder I32 in the base H8. The piston I33 in this cylinder is normally maintained in its lower position by spring I34 and is connected with the valve mechanism I39. In the position shown, air pressure is supplied by pipe II'I through cavity I38 to pipes H9 and H6.

When the air pressure is reduced in cylinder I 32, the pressure in cylinder I36 moves piston I35 upwards shutting off air supply from pipe I I! through cavity I38 in valve I 39 to pipe H6 and connecting this pipe to cylinder I36 where it connects to atmosphere by port I31. As the sub-atmospheric pressure is further reduced in cylinder I32, pipe H9 is cut ofi from cavity I38 and exhausted into cylinder I 36. As atmospheric pressure in cylinder I32 is restored the valve I39 is restored and air pressure is reestablished in pipes H9 and H6 from pipe In. It should be noted that the air in cylinder 65 is maintained by pipe H6 in the speed control position so that if this pipe exhausts, cylinder 65 exhausts and thereby produces a control effect. Pipe H9 may, similarly, exhaust cylinder 67 under speed control conditions. The air exhausted into cylinder I36 from pipes H6 and H9 has a tendency to raise piston I33 but this condition is substantially neutralized by the large orifice I31 connecting to atmosphere.

The air pressure in cylinder I32 is reduced by the Venturi tubes I25I26 as the device moves at speed along the track. It will be noted that the Venturi tube is symmetrical about its transverse axis and is adapted to pass air currents therethrough in either direction according to the direction of running and in order to obtain the Venturi effect in each direction a change over mechanism is provided which automatically connects cylinder I32 with the trailing Venturi tube. The Venturi efiect referred to is well understood in aerodynamics. The flow through the tube is accelerated from the increase in velocity and consequent loss of pressure caused by a reduction in the cross-sectional area or the tube. Its operation is pneumatic and it is not to be confused with the mechanical displacement of a vane by air currents.

The direction control of the venturi will be understood from Fig. 12. The blades I are suspended in the tube, one being pivoted at I42 at one end of the venturi and the other being pivoted at I44 at the opposite end. It is apparent that these blades will be deflected In the direction of the air current through the tube. A rotary. valve I49 is rotated by arm I48 connected by rods I45 and I46 with the blades I4I--I4I. This valve is provided with a cavity I29 which, when arm I48 moves to the right connects the port I28 with the passage I3I, and when arm I48 moves to the left port I30 is connected with passage I3I When the apparatus is in the neutral position as shown, a passage I5I shown in dotted outline connects passage I 3I with atmosphere.

It the vehicle carrying the venturi is moving to the left, the air current therethrough will be relatively towards the right. This moves the blades MI and thereby connects tube I26 with the cylinder I32. On the other hand, it the direction of movement of the vehicle is reversed, the blades I4I will be reversed and cylinder I32 will be connected with tube I26. Air is exhausted from cylinder I32 by the well known Venturi principle, proportionally to the speed oi! the vehicle hicle stops the air pressure in I32 is equalized through I6l,or may be equalized through the passage I35 as the Venturi eflect decreases.

This venturi is provided with side ports so that it is not materially influenced by adverse wind currents and the opposite cylinder I36 also receives air through the side port I31 so that variations in the density of the air,- due to tunnels. etc., are neutralized.

' The apparatus In the apparatus described it will be noted that the control mechanism is embodied in one casting and that long pipe connections are avoided,

the only pipes used being those to the stepping valve and to the speed control apparatus. The

control apparatus is embodied in a casting which replaces the engineer's brake valve, which casting is bored from either end for the operating cylinders and valves. The controlling valve is In the centre and the expansion chambers are built around it with the passages between the various parts formed in the casting. The air for operating the pistons comes from the opposite. end of the line so that a false operation cannot be obtained by the accidental closing of the pipes.

The forestalling or synchronizingvalves are embodied in the control apparatus as shown in Fig. 3 so that the apparatus is manipulated by handle 69 and by the handle 88 of the iorestalling valves. It should be noted that the walking beam arrangement for supporting stem 42 includes any equivalent floatin connection such as'a rack and pinion that may be substituted for this construction.

The speed control arrangement avoids the use of apparatus driven by the running gear of the vehicle, is automatically operative for both directionsand the tubes I25-I26 are mounted in a casting whichforms the cover of cylinder I32 so that the apparatus is compact and not likely to get out of order.

Itwill be noted that each operation of the st p-ping valve I lowers the walking beam 43 -to apply the brakes, but if a second operation were obtained without the corresponding operation of the forestalling valve, it would cancel the first operation. .This is avoided by wiring the control valve as indicated in Fig. 13. The disc I03a rotates with shaft I04 and carries the con'= tacts I56, I58, etc., in line with contact finger I60 and the contacts I55, I 51, etc., in line with the contact finger I 59, there being a. contact for each tooth in wheel I03. Contact finger I54 makes 5 contact with the inner and outer row of con-' tacts and by wire I53 connects to control magnet 3|. The handle 86 of the forestalling valve carres the contact plate I64 which is connected to wire I66 and in one position makes contact with finger I63 connected to wire I6I and in the opposite position makes contact with finger I65 connected to wire I62.

In-the position shown the circuit of 9! through wires I53 and I62 is interrupted at contact finger I65 until handle 88 is reversed. That is, 88 must be moved to synchronize with the movement of the stepping wheel I03 before 91 can be again energized. After 88 has been moved it will be observed that the next step of wheel I63 brings contact I54 and I55 into circuit with wire I6I and SI cannot be energized until 88 is moved to establish the circuit between I63 and I64. The

remaining part of the controlling circuit for 9| is not shown in this diagram.

It should be understood, that the forestalling valve may connect to pipe H9 oi the speed control device, Fig. 9, and thus be operative under different speed'conditions .irom pipe III; controlled by'valve 8|. This part,ior simplicity, is

- omitted from the drawings, being a duplication of the apparatus already illustrated.

OPERATION-CASE I Manual control of the brakes When the automatic control is released by air pressure in cylinders 65 and 61, the brakes are manually operated by handle 69. When in position a the pin 41 occupies slot SI and 44 may be raised to the extreme position. This raiscs valve I2 to its extreme position and main air supply is connected through I4, I3 and I5 with cylinder 22 which closes exhaust 28 and permits 34 to seat and connect MR with the train line,

- thus releasing the brakes. This is the running position.

When handle 69 is moved to position b, pin 41 occupies slot 52 and walking beam 53 is lowered with valve I2. This closes the air supply It and connects I6 with I6, reducing the air pressure in 22 and 23 by the volume of the expansion reservoir 20. This permits piston 26' to unseat valve 28 until the pressure in chamber 2'! is equalized with the pressure above the piston, after which the valve 28 is reseated. This causes a partial reduction of the train line pressure and a corresponding braking effect which is maintained by the reduced pressure above piston 26. This may be called a service application.

When the apparatus operates to apply the brakes, it is, in most cases, necessary to close the connection from the main. reservoir to the brake pipe, to prevent the brakes being released, or to insure quicker operation of the brake application. In the prior art this is usually provided for cation valve.

In this invention the brake feed pipe from the main reservoir is controlled pneumatically by the piston 34 and the slide valve 36 secured thereto as best shown in Figs. 14 and 15. This piston through a mechanicaliconnection with the appliresponds to the pressure in chambers 22, 23, and

a which are equalized through the ports25 and 31. The initial lowering oi the pressure in these chambers lowers the pressure above piston 34 to such an extent that the trainline pressure in chamber 33 raises the piston against spring 35 to the position shown in Fig. 15 in which the port 36a to the main reservoir is closed. When running conditions are restored, the air pressure in chambers 22, 23, and 35a. is restored from This reducing valve is not shown in the drawings. If It is connected with the main air supply the chambers 22 and 23 and the chamber 35a in which spring 35 is located magnet 9| aoaasao will normally stand at this pressure, while the pressure in the brake pipe 32 and the chambers 21 and 33 will stand approximately at seventy pounds pressure. This will cause the valve 28 to seat and the valve 36 to seat and establish connection from MR to pipe 32 through port 36a. When the pressure in chambers 22, 23 and the chamber 35a above the piston 34 is expanded into the expansion reservoir 28, the valve 28 is unseated and the valve 36 is unseated. This condition continues while the brake pipe pressure is being exhausted through the vent 29, and until a reduction has been made suificient to cause the remaining pressure in chamber 22 to close the port 28.

At this time the valve 36 may be again seated, depending upon the friction of the piston 34 in its cylinder and as it becomes seated, under these conditions, a, connection will be established. However, as soon as pressure from MR, begins to rise in chamber 33, piston 34 is raised, valve 36a is closed and the recharging is cut off.

When handle 69 is moved to position 0, the pin 4'! occupies slot 53 which lowers walking beam 43 and valve l2 to the next stage. This connects chamber 22 to expansion reservoirs 20 and 2| through ducts l6 and I1 and causes a further reduction of pressure on piston 26 which unseats valve 28 and releases the pressure in chamber 21 until the pressure above the piston is equalized by a further reduction of train line pressure and an increased application of the brakes caused thereby. This may be called an emergency application.

- When handle 66 is moved to position d, the pin 41 occupies slot 54 and the valve I2 is thereby lowered to its maximum extent. This connects chamber 22 with the expansion reservoirs I9, 28 and 2| through ducts l6; l1 and I8 and reduces the pressure on piston 26 to a low value. This unseats valve 28 to make the maximum train line reduction and maximum brake application.

The handle 69 can be moved from position a to position d as rapidly as the plunger 48 can be moved in the dash pot 49. The dash pot is regulated to prevent a sudden movement of the valve 12 under the action of spring 4|. It is apparent that the handle 69 can be moved from the position d towards position a to any extent so that the braking effect may thereby be regulated. When the handle is fully restored to position a air pressure from port I4 is connected through l to cylinder 22, reservoir 23 and cylinder 35a thus restoring running conditions by seating valve 28, closing the exhaust and connecting MR to train pipe 32. This manual operation is always obtainable under all conditions.

OPERATION-CASE II Automatic control of brakes The automatic control is obtained through the When this magnet is energized and the valve 88 synchronized with the stepping valve, air is supplied from pipe H2, through valve I08, and either of pipes 81, 98, through valve 8! to pipe 88 and valve 68 to cylinder 65 raising one end of walking beam 6|. A corresponding magnet operates with valve IQ-supplying air pressure to pipe 18 and through valve 66 to cylinder 61 raising the other end of walking beam 6|. maintained the valve I2 is maintained in the raised position as far as the automatic control is concerned.

Thus, as long as the air pressure is When the magnet 9| is deenergized valve I68 makes one step which vents the pipe under pressure connecting to valve BI and this will vent the cylinder 65 unless the synchronizing valve 88 is reversed. That is, the movement 01' the piston 99 must be forestalled to prevent the walking beam 43 being lowered, and the consequent immediate application of the brakes. After magnet 9! is deenergized a time interval must elapse before piston 99 is moved viz, until the pressure in the timing cylinder 91 is exhausted through the alarm whistle 95a. The sounding of the whistle is a Warning to operate the forestalling device and prevent an immediate ,brake application which will occur when cylinder 65 and the timing reservoir 88a are exhausted.

After the forestalling device has been oper-' ated and during the time 9i is deenergized, the air pressure to cylinder 65 is controlled by the speed of the vehicle through pipe H6. When the speed is low this pipe is supplied with air pressure from ill, but when the speed is above a predetermined value this pipe is vented and through it the air in 65 is vented and the walking beam 43 is lowered. As soon as BI is energized and piston 99 moved to the active position, piston 4a is moved to connect the air supply ll2 to the cylinder 65, thereby raising the walking beam and releasing the brakes.

The cylinders 65 and 6'! are controlled by similar mechanisms but they may operate under different speed conditions and the controlling magnets may be controlled over different portions of track. It will be noted that each cylinder lowers the walking beam to the same extent and the lowering eifects produced by one cylinder is added to the effects produced by the other cylinder. In practice it may be desirable to have the movements of the walking beam causedby 65 and 61 correspond with the movements of 44 in slots 52 and 53.

The lowering and raising of the walking beam by the cylinders 65 and 61 produce movements of valve l2 similar to that already described with corresponding braking effects. In the automatic operation it should be noted that the brakes are always applied after a time interval, when the controlling magnet is deenergized, if the forestalling device is not operated. but if this device is operated at the proper time, the brake application becomes subject to speed control.

OPERATIONCASE III Combined manual and automatic control It is apparent that the floating connection 43 mechanically connects the manual and the automatic controlling mechanisms and controls the brakes through the single valve l2. It is generally recognized in practice that if the brakes are properly controlled manually, the automatic control is unnecessary, but, on the other hand, if the manual control is released, or if it is applied to a lesser extent than that required by the automatic control, then the automatic conrol should become effective to apply the brakes to the extent whichthe manual control has failed to apply them. This result is secured in the present invention by making the operation of the manual control progressively suspend the operation of the automatic control as the manual control progressively applies the brakes and reversing this conditions as the manual control is released.

When the brake controller 69 is moved to position b to produce the first stage of braking, pipe 80 is out oif and slot connects with the slot 82 thus. supplying air pressure directly from while the manual control is operative. If pipes 'l8 and 80 are both vented by the automatic control while the manual control is in position c the manual control suspends the automatic control, but if the manual control is afterwards partially released by moving; handle 69 to position b then the slots 17 and 83 are disconnected and the connection between pipe 18 and slot 11 is restored and thecy linder 6] is vented through pipe 18. This lowers walking beam 43 to the extent of another stage of braking and the braking effect is the same as if the controller were :in position 0. The manual control thus suspends the automatic control when the automatic braking effects do not exceed those applied manually, but the automatic control is always effective for braking control in excess of the manual control.-

The brake controlling apparatus can be constructed in a variety of forms of which a typical arrangement has been selected to illustrate the working principles of the invention, other forms ofthe invention may be applied by those skilled in the art without departing from the intent and scope hereof.

This invention comprises a train control system and braking apparatus used in connection with the ordinary air brake systems. The system includes E. P. valve 9| which is responsive to traflic conditions on the trackway by any suitable controlling system and this valve in turn operates a stepping valve I 63 maijring one step for each control effect obtained fm m the trackway. The stepping valve mas connected, therewith, a pair of pipes, 8196 one of which is active to connect air pressure through a manually con-' trolled forestalling valve 8| to the brake controlling apparatus operated by cylinder 66 while the otheripipe remains inactive. When a control effect has been obtained the stepping valve is moved tochange the control, from the active to the inactive pipe and, under these conditions, the forestalling valve must be changed in posi-' tion, either before the stepping valve is operated or immediately thereafter so as to maintain the" air pressure in cylinder 66 and prevent a brake application.

The air supply to the stepping valve for operating the brake application valve is obtainedditest, under normal conditions, but is obtained through a speed control device H8 which connects by pipe 'I I 6 with the stepping valve. The speed control device operates to exhaust pipe I I6 at high speed and to connect air pressure. to the pipe at restricted speeds so that when a control effect is obtained it can be manually forestalled provided.the speed does not exceed a predetermined value.

g A pair of E. P. valves, similar to SI with the associated stepping valve, manual release and speed control are contemplated in the system, one

i said automatically controlled means.

of which operates at a lower speed than the other. These devices operate through the cylinder 64 and cylinder 66 and the walking beam 6| to move the slide valve l2 in the central part of the valve housing against spring 5|. The beam 43 is also operated manually by a;notched plate which is designed to lower the slide valve l2 in stages, each stage corresponding to a different degree of braking, When? the manual control is operated to the same extent as the automatic control through cylinder 64 and cylinder 66, the

automatie control is thereby suspended by supplying air to the cylinders 64 and66 through the manipulation of the manually operated valve.

However, if the manually operated valve is moved to the release position, when the automatic control is established, the automatic control immediately becomes efiective;

The brake pipe is vented by an equalizing valve which has pressiire on one side vented into a series of expansion reservoirs corresponding with the position of valve I2. In order, however, to.

provide an intermittent venting of the train line preference to a continuous venting during the brake application process, the equalizing valve has a double action in which it restricts the venting of the pressure above the valve and temporarily reestabiishes equalization, causing this valve to assumethe normal position and close the venting of the train line until further reduction has been made into the equalizing reservoir when it is againunseated to vent the train line and in this way an intermittentventing of the train line may be secured. 7 The brake valve with the equalizing valve is made in one casting in which'the valves are centrally. located and the expansion reservoirs are placed circinmferentiallyaround these valves so as to econoniize on space and eliminate outside pipe connections. 7 7 Speed control is obtained by a specifically degsigned Yenturi tube which is made double ended I and with slide ports for the air entrance. A 'valve is operated by the venturial action in reducing the atmospheric oressure bearing on this valve which moves to an extent corresponding with the speed or the vehicle. This valve, in turn, cooperates with 'the stepping. valve in the operation of the brake valve mechanism. 1

I Having thus described my invention, I claim: 1. A brake controlling mechanism for an air brake system comprising a brake valve for producing brake applications in stages, manual controlled means mechanically operating said valve and automatically controlled means operating said valve, each to a plurality of stages of braking,

1 said means openatively connected with each other arranged to independently operate said valve to apply the brakes, said manual controlled means having 7 means associated therewith operating pneumatically for suspending the operation by 'j 3. Abrake controlling mechanism for an air brake system comprising a brake valve for producing a brake application, manual controlled means and automaticaily controlled means connected for operating said valve said manual control means having means associated therewith which, when operated to apply the brakes pneumatically suspends the operation of said automatically controlled means and when operated to release the brakes restores the automatic control.

4. A brake controlling mechanism for an air brake system comprising a brake valve for producing brake applications in stages, manual controlled means and automatically controlled means mechanically connected for operating said valve for different stages of braking, the automatically controlled means being dependent pneumatically upon the manual control means for braking to the same extent as that produced by the manual control means and being independent of the manual control for increased braking effects.

5. A brakecontrolling mechanism for an air brake system comprising a brake valve for producing brake applications in stages, manual controlled means and automatically controlled means each operating said valve to a plurality of stages of braking, the manual controlled means, when in the application position, suspending the operation of said automatically controlled means for the same degree of braking only and restoring the automatic control when operated to release the brakes.

6. A brake controlling mechanism for an air brake system comprising a brake valve for producing brake applications in stages, manual controlled means for operating said valve, automatically controlled means comprising a cylinder with a piston for independently operating said valve and means whereby said manual controlled means controls the air supply to said cylinder.

7. A brake controlling mechanism for an air brake system comprising a brake valve for producing brake applications in stages, manual controlled means for operating said valve, automatically controlled means comprising a plurality of cylinders for operating said valve and means whereby said manually controlled means controls the air supply to said cylinders in different positions.

8. A brake controlling mechanism for an air brake system comprising a brake valve for pro: ducing a brake application, automatically controlled means comprising a cylinder for operating said valve, a speed control device and a stepping speed control valve.

10. A brake controlling mechanism for an air brake system comprising a brake valve for producing a brake application, a. spring normally acting to move said valve to the application position, a motion plate having a plurality of steps and a. plunger controlled by each step of said motion plate and operating said valve.

11. A brake controlling mechanism for an air brake system comprising a. brake valve for producing a brake application, a spring normally acting to move said valve to the application position, a manually positioned motion plate, a piling er controlled by said motion plate, and a dash pot restricting the action of said plunger, said plunger operating said valve.

v 12. In a brake controlling mechanism for an air brake system for a vehicle, the combination, a brake valve for producing a brake application, a stepping valve controlling the operation of said brake valve, a magnet controlling the operation of said stepping valve and means, manually controlled, for preventing said magnet from making a succession of steps of said stepping valve.

13. An article of manufacture comprising a brake valve housing having a central cylinder with a manually operated valve therein and a second cylinder axially aligned with the first cylinder and having a piston therein controlling a valve by the difference in pressure on each side of said ,piston and an expansion reservoir surrounding said first cylinder and having a controlled connection with said second cylinder.

14. An article of manufacture comprising a brake valve housing having a central cylinder with a manually operated valve therein and a second cy'inder axially aligned with the first cylinder and having a piston therein controlling a valve by the difference in pressure on each side of said piston, an expansion reservoir connected with said second cylinder, said connection being controlled by said manually operated valve.

15. A braking system for a railway vehicle comprising an air brake mechanism, a valve controling said mechanism, means normally ho ding said valve in the non-controlling position means for rendering said holding means inactive and a Venturi tube mounted on said vehicle controlling said valve when said holding means is nactive.

16. A brake controlling system for a railway vehicle which operates in both directions, comprising an air brake mechanism, a valve controlling said mechanism, a double ended Venturi tube mounted on said vehicle having a longitudinal restricted air passage with end openings at right angles to said passage, means for deflecting air through said passage and means controlling the operation of said valve by said Venturi tube.

17. A brake controlling system for a railway vehicle which operates in both directions, comprising an air brake mechanism, a valve controlling said mechanism, a doub e ended Venturi tube mounted on said vehicle having a longitudinal restricted air passage with end openings at right angles to said passage, means for defleeting air currents through said passage, 8. tube in said restricted passage controlling said valve and means controlling the orifice of said tube by the direction of the air currents through said passage.

18. A brake controlling system comprising a brake valve having a cylinder with an equalizing piston, an exhaust valve controled by said piston, an expansion reservoir connected by a port with said cylinder and a valve operated by said piston for opening and closing said port.

19. A brake controlling system comprising a mechanism having a cylinder with an equalizing piston, an exhaust port, and an expansion reservoir connected with said cylinder by a port, said piston in one position closing said exhaust port and opening the port to said reservoir and in another position opening said exhaust port and closing the port to said reservoir.

20. In an air brake system, the combination, a brake pipe, a vent port, an equalizing valve connecting said brake pipe with the vent port,

a piston controlling said valve, means for equalizing the pressure on said piston to close said vent port, means for releasing the pressure on said piston to open said vent port and means operated by said piston controlling therelease of pressure on said piston.

21. Inan air brake system, the combination, a brake pipe, a vent port, an equalizing valve connecting said brake pipe with said vent port, a piston controlling said valve, means for equalizing the pressure on said piston to close said vent port, and meansfifor releasing the pressure on said piston intermittently to open said vent port, said releasing means being controlled by said piston.

22. In an air brake system, the combination, a cylinder with. an equalizing piston therein a port in each end of said cylinder, means associated with said piston for closing the port at;

one end and opening the port at the opposite end of said cylinder and when the piston is reversed for reversing this condition, an air brake pipe connected with one of said ports and an equalizing pressure connected with the other port.

23. In a brake controlling system for a vehicle, the combination, a brake valve for producing a brake application, a stepping valve controlling the operation of said brake valve, a magnet controlling the operation of said stepping valve and means preventing a succession of steps of said stepping valve when said valve is in the application position.

24. A brake controlling mechanism for an air brake system comprising a brake valve for producing a brake application, manual controlled means for operating said brake valve, automatic controlled means for operating said brake valve and a walking beam connecting said means with said brake valve;

25. A brake controlling mechanism for an air brake system comprising a brake valve for producing a brake application, a plurality of automatically controlled means for operating said brake valve anda walking beam connecting said.

means with said: valve.

26. A brake controlling mechanism for an air brake system comprising a brake valve for producing a brake app'ication, a plurality of means for operating said brake valve and a compound walking beamconnecting said *means with said valve.

27. A brake controlling mechanism for an air brake system comprising a brake valve for producing a brake application, a plurality of means including a motion plate for operating said valve and a walking beam connecting said means with said valve.

28. A braking system for a railway vehicle comprising an air brake mechanism, a valve controlling said mechanism, means normally holding said valve in the non-controlling position, and a Venturi tube on said vehicle having a iongitudinal restricted air passage with an end opening at right angles to said passage, means'for deflecting air through said passage, said Venturi tube controlling said valve when said controlling means releases control or said valve.

29. In a controlling system, the combination,

a control valve having an active and an inactive position, a magnet when energized, maintaining said valve in the inactive position, a Venturi tube and a valve controlled thereby for controlling said first named valve when said magnet is deenergized.

30. A brake valve comprising a cylindrical housing with a valve therein having a projecting stem and a motion plate passing around said cylinder and operatively connected with said stem for operating said valve.

31. A brake valve comprising a cylindrical housing with a valve therein said housing having a central projecting stern and a rotary valve centered about said stem to be operated without interfering with the free movement of said stem.

34. A brake valve for an air brake system comprising a control valve biased by a spring to the application position and a dash pot for retarding the action of said valve towards the control position.

35. A mechanism for controlling a braking system in stages comprising a first device automatically operated for operating said mechanism to the first stage of braking, asecond device also operating the mechanism to the first stage of braking, each device operating independently of the other, and said devices when operated at the same time co-operatively operating said mechanism to the second stage of braking.

36. A mechanism for controlling a. braking system in stages comprising a plurality of means, automatically operated, each for independently operating saidmechanism to the same stage of braking and for cooperatively operating said mechanism to two stages of braking and manually operated means for operating said mechanism to three stages of braking.

37. A mechanism for controlling a braking system in stages comprising a plurality of means, automatically operated from the track, each, for independently operating said mechanism to the same stage of braking and for cooperatively operating said mechanism to two stages of braking and manually operated means cooperating with said automatic means to increase the stages of brake application, but not to release the stages 

